The present device relates to a piezoelectric vibrator mounting system for generating an ultrasonic wave by using a piezoelectric vibrator to atomize a liquid.
In general, a nebulizer utilizing the phenomenon that, when a ultrasonic wave is radiated from inside a liquid toward a liquid surface, a water column is formed thereon at a prescribed ultrasonic wave intensity or above, and, the liquid is atomized, is widely utilized as a room humidifier.
FIG. 1 shows a conventional piezoelectric vibrator mounting system for holding a piezoelectric vibrator used in such a liquid atomizer for generating the ultrasonic wave so as to be able to energize the piezoelectric vibrator. In FIG. 1, the piezoelectric vibrator 1 for generating the ultrasonic wave has a structure wherein an ultrasonic wave radiating electrode surface 2A provided on the surface of the piezoelectric vibrator 1, a marginal electrode 2A' formed on a peripheral portion on the rear surface and connected to said surface 2A and a counter electrode 2B are provided in the approximately central portion on the rear surface of the piezoelectric vibrator 1. The piezoelectric vibrator 1 is excited by a high frequency exciting circuit at a frequency of the range of 1.about.3 MHz. The piezoelectric vibrator mounting system 10 comprises an outer casing 11 and an inner casing 12 both made of an insulating material, an elastic annular holder 13 made of a rubber or the like and having a U-shaped cross section, an annular electrode member 14 for contact with the marginal electrode 2A' and another electrode member 15 for contact with the counter electrode 2B.
The piezoelectric vibrator 1 has the annular electrode member 14 inserted into the groove 16 of the elastic annular holder 13 with the U-shaped cross section as superposed on the marginal electrode 2A' in close contact therewith. It is easy to atomize a liquid, so that the piezoelectric vibrator 1 is inclined for the horizontal level. It is able to keep its watertightness by the elastic annular holder 13 with the U-shaped cross section. Then, the elastic annular holder 13 is inserted into the inner casing 12 with a bottom surface superposed on the annular electrode member 15. After required lead wires are connected to the tongue-like portions 14A and 15A of the electrode members 14 and 15, respectively, which are penetrated through the slit-like openings 17 of the inner casing 12 down to the rear side thereof, the inner casing 12 is fixed to the outer casing 11 formed with lead wire leadout grooves 18 in advance.
Since the conventional piezoelectric vibrator mounting system shown in FIG. 1 has employed the elastic annular holder 13 with the U-shaped cross section, extremely troublesome handwork has been required for inserting the superposed piezoelectric vibrator 1 and the annular electrode member 14 into the groove 16 of the holder 13, which has reduced the efficency and effectiveness of an automated assembling process. Further, since the inner casing 12 has been provided separate from the outer casing 11, the number of parts and assembling man-hours have been apt to increase and subsequently manufacturing cost has been high.